DESCRIPTION: (Applicant's Abstract) The proposed study has two overall goals. First, it will monitor changes in treatment practices in the nation's outpatient drug abuse treatment units to determine the extent to which they are meeting known or desired standards of care. Information will be gathered on several important treatment practices, including: treatment duration and intensity; clients' use of primary health care, mental health care, and social services; HIV prevention practices; availability of special services for women and ethnic minorities; and methadone dose levels. Second, this study will examine how key organizational and community factors (e.g., unit ownership) account for change and variation in treatment practices. For example, how are various managed care arrangements affecting treatment duration and intensity, and clients access to social and health services? To achieve these goals, the National Drug Abuse Treatment System Survey (NDATSS) will be continued in 1999. The 1999 data will give us a current picture of treatment practices across the nation (n=600 treatment units). Further, with the addition of the 1999 survey, we will have data from a representative national sample of outpatient nonmethadone and methadone units for 1988, 1990, 1995, and 1999. The majority of treatment units to be included in the 1999 sample (n=387) have already participated in NDATSS in 1988, 1990, and 1995. Thus, we will be in a strong position to monitor changes in treatment practices over a decade (1988-1999), and to make causal inferences about these changes that can inform both policy and practice.